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Recurrence of morphea after successful ultraviolet A1 phototherapy: A cohort study
Rebecca Vasquez1, Aysha Jabbar2, Fatima Khan2
1Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, Texas.
Background:
Studies support efficacy of ultraviolet (UV)A1 phototherapy, but little is known about recurrence after successful UVA1 treatment.
Objective:
We sought to determine the frequency of recurrent activity after UVA1 phototherapy and variables associated with recurrence.
Methods:
This was a case series and prospective cohort study of patients treated with UVA1 phototherapy with minimum 6 months of follow-up. Demographics, clinical features, and cumulative UVA1 dose were analyzed for association with recurrence.
Results:
Of 37 patients, 46% (n = 17) had recurrence of active morphea lesions after successful UVA1 phototherapy. Two-year and 3-year (after the last UVA1 phototherapy treatment) recurrence rates were 44.5% (95% confidence interval 30.1%-62.2%) and 48.4% (95% confidence interval 33.2%-66.1%), respectively. The only variable associated with recurrence was duration of morphea before UVA1 (P value = .02, hazard ratio 1.15, 95% confidence interval 1.06-1.27).
Limitations:
The sample size limits conclusions.
Conclusion:
With the exception of increased duration of morphea, risk of recurrence is no different in adults and children, or between morphea subtypes, skin types, and medium- to high-dose regimens. This indicates treatment doses in the medium-high UVA1 range are adequate with respect to frequency of recurrence.
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